launcher: bump version for new release

Change-Id: I8a39630d482fc389cf497399102f795d7e576ff9
Reviewed-on: https://gerrit-review.googlesource.com/c/git-repo/+/294122
Reviewed-by: Michael Mortensen <mmortensen@google.com>
Tested-by: Mike Frysinger <vapier@google.com>

repo

@@ -147,7 +147,7 @@ if not REPO_REV:
   REPO_REV = 'stable'
 
 # increment this whenever we make important changes to this script
-VERSION = (2, 11)
+VERSION = (2, 12)
 
 # increment this if the MAINTAINER_KEYS block is modified
 KEYRING_VERSION = (2, 3)